TS 1391

TS 1391 is a withdrawn documentation standard that addresses the format and presentation of official letters prepared on a typewriter. Its subject is the common structure used to keep formal correspondence legible, consistent, and orderly across administrative communication.

What formal correspondence means in practice

Formal correspondence is the written channel used by institutions to exchange information in a controlled and recognizable form. In this field, clarity about who issued the document, who it is addressed to, and what administrative purpose it serves is essential. For typewritten documents, line layout, heading placement, page appearance, and overall formatting consistency become especially important because they support reading, filing, and traceability in official workflows.

The general coverage of this standard

Based on the supplied scope, the standard is focused on official letters written with a typewriter. Its concern is therefore not handwriting in general, but the formatting needs created by machine-produced text. Under a title such as official correspondence rules, one would typically expect attention to the placement of document elements, the organization of the text, and the institutional presentation of the letter style; however, for this record only the typewritten official-letter context can be confirmed.

Because the standard is withdrawn, it should be read as a historical reference to the correspondence practice of its time rather than as a current rule set. Even so, it remains useful for understanding how official document design, internal communication, and archival order were standardized in a typewriter-based office environment.